Function fetchSockets

packages/socket.io-adapter/lib/cluster-adapter.ts:570–614

(opts: BroadcastOptions)

  }

  async fetchSockets(opts: BroadcastOptions): Promise<any[]> {
    const [localSockets, serverCount] = await Promise.all([
      super.fetchSockets(opts),
      this.serverCount(),
    ]);
    const expectedResponseCount = serverCount - 1;

    if (opts.flags?.local || expectedResponseCount <= 0) {
      return localSockets;
    }

    const requestId = randomId();

    return new Promise((resolve, reject) => {
      const timeout = setTimeout(() => {
        const storedRequest = this.requests.get(requestId);
        if (storedRequest) {
          reject(
            new Error(
              `timeout reached: only ${storedRequest.current} responses received out of ${storedRequest.expected}`,
            ),
          );
          this.requests.delete(requestId);
        }
      }, opts.flags.timeout || DEFAULT_TIMEOUT);

      const storedRequest = {
        type: MessageType.FETCH_SOCKETS,
        resolve,
        timeout,
        current: 0,
        expected: expectedResponseCount,
        responses: localSockets,
      };
      this.requests.set(requestId, storedRequest);

      this.publish({
        type: MessageType.FETCH_SOCKETS,
        data: {
          opts: encodeOptions(opts),
          requestId,
        },
      });
    });
  }

  override async serverSideEmit(packet: any[]) {
    const withAck = typeof packet[packet.length - 1] === "function";